Limitations of the High - Low C - V Technique for MOS Interfaces With Large Time Constant Dispersion

We discuss the limitations of the high-low
CV
technique in evaluating the interface trap density (
D
_IT
) in MOS samples with a large time constant dispersion, as occurs in silicon carbide (SiC). We show that the high-low technique can seriously underestimate
D
_IT
for samples with large time constant dispersion, even if elevated temperatures are used to extend the range of validity.